This invention relates to herbicides particularly to herbicides that contain as active ingredient N-substituted-.DELTA..sup.1 -tetrahydrophthalimides. The invention also relates to said N-substituted .DELTA..sup.1 -tetrahydrophthalimides.
The method of manufacture and physical properties of some N-substituted-tetrahydrophthalimides are known in the art. For example, it has been reported in Berichte der Deutschen Chemischen Gesellschaft 1903 pp. 996-1007 that N-substituted-.DELTA..sup.1 -tetrahydrophthalimides were obtained by heating .DELTA..sup.1 -tetrahydrophthalic anhydride and primary amine in an alcoholic solution. Reference is made to physical properties such as crystal form, melting point and the like with regard to N-phenyl-.DELTA..sup.1 -tetrahydrophthalimide, N-(p-hydroxyphenyl)-.DELTA..sup.1 -tetrahydrophthalimide, N-(p-methoxyphenyl)-.DELTA..sup.1 -tetrahydrophthalimide and N-(p-ethoxyphenyl)-.DELTA..sup.1 -tetrahydrophthalimide. This report is referred to in Chemisches Zentralblatt 1906, II, pp. 876-877.
It should be understood that the disclosure in said prior publications is limited only to the method of manufacture and physical properties of specific N-substituted-.DELTA..sup.1 -tetrahydrophthalimides.